sedimentary
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Hardness: 6.5-7 Mohs. Color: Grayish-brown. Luster: Waxy to dull. Structure: Cryptocrystalline. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.
- Hardness
- 6
- Color
- Grayish-brown
- Luster
- Waxy to dull
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Physical properties
Hardness: 6.5-7 Mohs. Color: Grayish-brown. Luster: Waxy to dull. Structure: Cryptocrystalline. Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.
Formation & geological history
Formed in marine environments from the accumulation of siliceous remains (diatoms/radiolarians) or by chemical precipitation. This piece has been anthropogenically modified by flintknapping.
Uses & applications
Archaeological artifact; historically used as a projectile point. Now high value for collectors and historical research.
Geological facts
This is a stone tool made using the conchoidal fracture properties of chert to create sharp edges. Chert is also commonly known as flint when found in chalk or marl.
Field identification & locations
Identified by unnatural flake scars, notched base, and symmetrical triangular shape. Commonly found in creek beds or agricultural fields in regions with prehistoric habitation.
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